An internal combustion engine is understood to be known in the market, that is equipped with a particulate filter, and in which the soot burn-off is controlled or checked, in order to protect the particulate filter. Such a system, with the corresponding method, is discussed in DE 10 2007 010 189 A1, in order to regulate the temperature of the exhaust gas during a regeneration process of a particulate filter.
In the regeneration operation of a particulate filter, a high oxygen supply in the overrun phase of the internal combustion engine would, for instance, lead to a locally reinforced soot burn-off. At lower engine speeds, the exhaust gas mass flow is too low for a sufficient heat dissipation, which may lead to thermally conditioned damage to the particulate filter. For this reason, by closing the throttle valve and opening the exhaust gas recirculation valve, exhaust gas may be pumped in circulating fashion, in order to make no, or little oxygen available to the particulate filter. In the case of a leakiness of the air system or its components, such as an untight throttle valve, this measure no longer acts within the desired scope, and the temperature stress of the particulate filter could become greater than desired.